CSC305 Lecture 13

Individual Software Design and Development
Singleton
(202410)

Transcript

1. Dr. Javier Gonzalez-Sanchez javiergs@calpoly.edu www.javiergs.info o ffi ce: 14 -227 CSC 305 Individual Software Design and Development Lecture 13. Singletons and Blackboards
2. Previously
3. Scenario 1 3
4. Scenario 2 4
5. Scenario 3 5
6. GameMain 6
7. Singleton
8. GoF Patterns 8
9. Singleton 9
10. Singleton class MainApp { public static void Main(String []a){ Singleton s1 = Singleton.getInstance(); Singleton s2 = Singleton.getInstance(); // Test for same instance if (s1 == s2){ // true - Objects are the same instance } } } 10
11. Singleton class Singleton{ private static Singleton _instance; private Singleton() {} public static Singleton getInstance(){ if (_instance == null){ _instance = new Singleton(); } return _instance; } } 11
12. Test Yourselves
13. Lab 13
14. Blueprint 14 M a in Dr a wAre a Dr a wAre a Listener Repository
15. Main 15
16. DrawArea 16
17. DrawAreaListener 17
18. Repository 18
19. Questions 19
20. Lab
21. Lab 21
22. • Can we draw the last 10 dots only? • Can we make darker the newest dot and light-gray (white) the oldest one? • Connect all the dots with a line, but instead of following the order in which they were clicked, connect them based on the shortest distance between each dot.
23. Test Yourselves
24. Let’s Work 24
25. CSC 305 Individual Software Design and Development Javier Gonzalez-Sanchez, Ph.D. javiergs@calpoly.edu Summer 2024 Copyright. These slides can only be used as study material for the class CSC305 at Cal Poly. They cannot be distributed or used for another purpose.